Mechanically set well packer



Aug. 29, 1961 E. H. CLARK, JR., ET AL 2,998,073

MECHANICALLY SET WELL PACKER Filed Aug. 11;1958 5 sheets-sheet 1 u,|l|\ H W/C A 72% M Md ATTOQNEYS Aug- 29, 1961 E. H. CLARK, JR., ETAL 2,998,073

MECHANICALLY SET WELL PACKER 3 Sheets-Sheet 2 Filed Aug. ll, 1958 E'AQNEST H. CLAQK, JQ. WILLIAM MVEQS INVENTORS TTOQNEYS Aug. 29, 1961 E. H. CLARK, JR., ET AL 2,998,073

MECHANICALLY SET WELL PACKER Filed Aug. 1l, 1958 3 Sheets-Sheet 3 INVENTORS EAQNEST H.CLAI2I ,JI2, WILLIAM D. MVEQS BY TTOQNEYS United States Patent O 2,998,073 TMEGHANICALLYI SETWELL PACKER Earnest H. Clark, Jr., Downey, and William D. Myers, Norwalk, Calif., `assignors to Baker il Tools, Inc., Los Angeles, Calif.,a corporation of California Filed Aug. 11, 1958, Ser. No. 754,330 1'4^Claims. (Cl. 166-134) The presentinvention relates to subsurface well bore equipment, and more particularlyto well packers adapted to be anchored infpacked-of condition in well bores to perform-certain desirable operations therein, Vsuch as cementing, lacidizing, producing,formation fracturing, testing, or bridging.

An object of the invention.' is to provide a well packer having normally retracted slips and packing which can be retained more-securely in 4retracted positions during runningof the well packer? in a well bore, assurance being had that the parts will not be released and expanded prematurely.

Anotherobject of the invention is to provide a well packer having outwardly expandible parts normally retained Vinretractedposition by the use of shear screws, or the like, in which theshear screws can :be made stronger, and in which certain parts of the packer are not retained in retracted position by-shear screws.

VA further object of the invention is-to provide an improved mechanical device .for eifecting outward expansion of certain'wellpacker parts,.such as casing engaging slips, when Ithelsetting location of the packer in the well bore has been reached.

An-.additional object of the invention'is to provide a well tool embodying improved means for retaining. the vnormallyretracted lsegmental slips of the vtool in alignment while they are retracted and while they arezbeing expanded outwardly.

This inventionpossesses:manyother advantages, and has Vother objectswhich :may be made more .clearly .apparent from .a consideration of a. form. in which it may be emzbodied. This form is shown in the :drawings accompanying and forming part of the present specification. .'It. will A:now hedescribed in detail, for'thepurposenof illustrating .the general principles :of the invention; .but :it is to be understood that such detailed description is 4'not .to betaken in a limitingzsense, since :the scope .of .the .invention is :best .denedzby the app ended claims.

Referring to rthe;drawings:

'FIGURE'lqis a V.combined side elevational view and `longitudinal section through a well packer apparatus, with its parts in their initial or retracted position;

FIG. .2 is a lview similarto -FIG. l illustrating the well packer partially. set in awell casing;

FIG. 3 is ;an;enlarged viewsimilarvto FIGS. l and 2 showing well-packer fully set. within the well casing;

FIG. 4 isa cross-section taken along ;the line:4-.- 4. on FIG. 3;

4l:"IG.15f.is.. an.y enlarged fragmentary section .through ,the latch or locking portion of the -well packer;

PIG. `6.-is.,aview similar toFIG- 3 illustrating the central-passage through "thee-packer closed;

fFIG. 7 s;a view similar .to FIG. 3 illustrating ithe central-.passage through the packer closed against 'upward dlow of uidtherethrough and Athesettingniechallismxof the apparatus removed. therefrom.

.Thewell packer A illustrated in the drawings-isadapted to be anchored innpacked-ol condition in -a'well casingfB. It is run in the f'well'casing, vor similar conduit string, by means .of a setting, tool 3C, the upper portion-ofzwhieh -is attachedfto Vthe .lowenendn of a tubular runningin string D, `such as .tubing ordrill pipe vextending to the, Ltop .of the hOle.

Thewellpackeriucludesatubular body 10 havingian 2,998,073 Patented Aug. 29, 1961 upper-ring L11 threadedly securedthereto, against which a set of upper segmental slips .1 2 are retained initially. These segmental slips have upwardly facing wickers 13 adapted to embed themselves in the wall of the well casing B when the slips are expanded outwardly thereagainst. They also have inner surfaces .14 inclined in an upward and inward direction and engaging a companion externally tapered surface y15 on an upper expander 16 initially releasably retained to the 4body of the tool by one or more shear screws 17. Surrounding the body is a packing sleeve 18, of rubber or rubber-like material, which is disposed initially in a retracted position with its upper end engaging the upper expander 16 and its lower end a lower expander 19 secured initially to the body of the toolby one or more shear screws 20. This lower expander has an external expander surface 21 tapering downwardly and inwardly, which engages companion inner tapered sur-faces 22 on a lower set of segmental slips '-23 held initially in retracted position by shear screws 24 attaching them .to the lower expander. These lower slips have downwardly facing wickers or teeth 25 adapted to .engage the wall of the well casing B when expanded outwardlythereagainst by the lower expander 19. -Initially the -lower slips rest .upon the upper abutment end 26.=.of a'body extension 27 threadedly secured to the body 10 ,0f.the .tool, this body extension having a cylindrical valve seat 28 therein and also .a tapered valve seat 29 below the. cylindrical valve seat. The cylindrical valve seat may contain a side seal r-ingi30, made of rubber or rubber-like. material, whereas, the tapered valve seat 29 may also have a rubber or rubber-like sealing element 31 contained therein for sealing against a companion valve vmember-132.

The :upper'set of slips 12 is retained initially .in alretracted vposition by a plurality of longitudinally extending retaining. pins 3 3. As illustrated, a pair vof such retain- `ing pins 5are slidably disposed in companion longitudinal .bores 34 in each slipsegment 12, `the retaining pins extending through aligned longitudinal holes 35 in the body ring 11. The retaining pins have reduced diameter shank portions 36 extending through the lower head `37 of a release sleeve 38, .the pins beingclamped lto this head by lnuts .39A threadedon theirA upper ends; thati bear against .the upperside of the head, pulling the pin shoulders ,4 0 Avagainst the lower side-ef the head. Inadvertent loosening of the-nuts 39' isprevented bya lock m1t 41 threaded onthe s tern of eachretaining pin 33. When the pins aref-pulled upwardly out of lthe sockets or bores 34 in the slip segments '12, compression springs 42 can shift the slips downwardly along the upper expanderl and ra- ,dially outwardly intoV engagement with thewall of the well casing :13. [Each of said springs is disposed in a .longitudinal socket'. 43 in the `mid-portion of each ,slip segment, Ithe .upper end of the spring bearing against the vlowerV surface of thebody ring A11.

.-When the retainingl .pins 33 are disposed `in -the upper slip segments 12, the `latter areV held in their upwardposi- Ation-against zthe body ring 11, and also retracted inwardly against .the peripheryof thehodynltl, the springsg42 then being in a highlyeompressed state. Uponpulling of the pins 33 upwardly from the sockets 34, the springs can propel segmental slips 12tdownwardly along theexpander 16 and voutwardly into engagementwith the-wall of the .well casing.

Assurance .isyhad that the upper segmental slips 1 2 vwill shift downwardly, Vwhile remainingin transverse aligfment with respect to one another, by providing transverse aligning pins 46 within and between the slip segments.

' Thus, .each slip segment `,12.has a hole 47 therein at each ,-ofdts side portions inwhich an aligning pin-46 is disposed,

slip segment, as shown most clearly in FIG. 4. The aligning pin 46 may have a press fit in the bore 47 in one section and a slidable iit in the bore 47 of the adjacent segment, or it may be slidable in the bores lof both segments. The laligning pins 46 retain all of the slip segment-s 12 in the same transverse plane, while permitting them to slide along the aligning pins 47 when they are shifted radially Youtwardly by the action of the spnings 42 forcing the slips 12 downwardly along the tapered surface 15 of the upper expander 16. The aligning pins 46 .insure the retention of the slips 12 in alignment when in retracted position, and during their entire movement to their fully expanded position in anchoring engage ment with the wall of the well casing B. Q

The retaining pins 33 not only hold the slips 12 in retracted position, but they prevent such slips from being yshifted inadvertently down along the expander 16. The lower set of segmental slips 23 is yalso prevented from being prematurely tripped and expanded by providing an inner shoulder 50 on each segment 23 engaging the lower side of a split, contractile retainer ring 51, the upper end of which bears against a downwardly facing shoulder 52 on the'body 10. During lowering of the 4apparatus in the well casing, any foreign matter that might tend to become wedged between the lower slips 23 and the wall of the well casingB is prevented from shearing the screws 24 attaching the lower slips to the expander 19, by virtue of the fact that the upward force on the slips is transferred through the segmental ring 51 to the body of the tool. The segmental ring, however, does not interfere with upward shifting of the lower slips 23 along the lower expander 19 to secure their ontward` expansion into engagement with the wall of the well casing, as described hereinbelow.

The apparatus is run in the well casing by means of a tubular mandrel 55, including an upper section 56 having an upper threaded pin 57 for threadedly securing the mandrel-to the lower end of theV tubular string D. This upper section is threadedly attached to `a lower section 58 extending through the central passage 59 through the body 10 and also through Ithe valve seats 28, 29 surrounding such passage. The mandrel carries a suitable side seal structure 60 held against a shoulder 61 on the lower mandrel section 58 by -a retainer sleeve 62 held against the upper portion of the seal structure by the lower end of the upper mandrel section 56. This retainer sleeve has an outwardly directed stop flange 63 ladapted to engage a companion upwardly facing shoulder 64 on the body 10 of the tool. Leakage of uid between the mandrel l55 and the wall of the body passage 59 is prevented by the side seal 60 and also by the engagement of the cylindrical seat 28 and its seal ring 30 with the periphery of the lower mandrel section 58.

The mandrel 55 is releasably secured to the body 10 of the tool by a threaded nut 67 threadedly secured within the upper threaded box`68 in the body of the tool, the threads being left-hand. This nut is slidably splined to the mandrel 55 by securing an elongate longitudinally extending key 69 to the mandrel, which is slidably received within a companion keyway 70 extending lengthwise of the nut. When the nut 67 is threaded fully within the threaded body box 68, its lower end engages the shoulder 63 provided by the upper end of the retaining sleeve 62. Y

The setting tool includes the mandrel 55 and nut 67 arrangement and also the lrelease sleeve 38 that carries the retainingpins 33. The upper end of this release sleeve has ia threaded headl portion 7,5 Vthreadedly connectedto the lower threaded portion 76 ofthe drag body 77 of a drag device 78 surrounding ftheY mandrel 55.V The threaded connection 7'5, 76 is left-hand in order that right-hand rotation of the release sleeve. 38 will cause Vit'to thread upwardly along the drag body 77 until it is completely unthreadedrtherefrorn, `as described herein- Ibelow.'

The lower portion of the drag body 77 has the lower ends of circumferentially spaced, outwardly bowed drag springs 79 secured thereto, which are adapted to frictionally engage the wall of the well casing B, the lower ends being secured to the drag body by an encompassing retaining ring 80 attached to the body by screws 81. The upper ends of the outwardly bowed springs 79 are secured to van upper collar 82, slidable on the upper portion of the drag ybody 77, by an' upper retaining ring 83 encompassing the springs and attached to' the collar by a plurality of screws 84. The'drag body 77 itself is movable longitudinally with the mandrel '55, the latter, however, being capable of rotation therewithin by providing a swivel connection therebetween. Thus, a split ring 85 is mounted in a peripheral groove 86 in the upper portion of the mandrel section 56, and is received within an opposed circumferentially continuous groove 87 delined between the upper end of therdrag body 77 and a drag body nut 88 threadedly mounted thereon.

The apparatus is run in the well casing B with the parts disposed in the relative positions shown in FIG. l, in which the upper and lower segmental slips 12, 23 and packing sleeve 18 yare in retracted positions, the retaining pins 33 `being disposed fully within the bores 34 of the upper segmental slips 12, with the springs 42 in their maximum compressed state. The release sleeve 38 is threaded within the drag body 77 of the drag device, the nut 67 being fully threaded within the body 10 of the apparatus. The Iapparatus is lowered in the well casing with the outwardly bowed springs 79 of the drag device 78 sliding frictionally along the wall of the well casing.

During such downward movement, any debris in the well bore is pushed ahead of the apparatus by a junk catcher and feeler 90 having longitudinal slots 91 therethrough, which can be threadedly secured to the lower portion of the lower body member or extension 27.

When the location in the well bore is reached at which the well packer is to be anchored in packed-olf condition, the tubing string D and mandrel 55 are rota-ted to the right, causing the entire packer structure A to rotate with it, as well as the release sleeve 38. However, fthe drag device 78 is prevented from rotating by the frictional engagement of its bowed springs 79 against the Wall of the well casing. Accordingly, rotation of the entire apparatus, with exception of the drag device, will result 4in a relative upward feeding of the release sleeve 38 along the drag body 77 in view cf their left-hand threaded interconnection 75, 76, the release sleeve moving upwardly and pulling the retaining pins 33 in an upward direction until they have been pulled completely from the bores -34 of the upper segmental slips 12. When this occurs, the slips 12 and the springs 42 are released, the springs shifting the slips downwardly along the upper expander 16 and radially outwardly into engagement with the wall of the well casing. As described above, the aligning pins 46 insure that the slip segments 12 will retain their alignment with respect to one another. When the slips 12 are released, they may shift circumferentially of the body during their outward expansion, but, if such shifting occurs', the pins 46 will still maintain their alignment.

Usually, the tubular string D, the mandrel 55 and the packer apparatus as a whole Vare rotated to the extent at which the head 75 of the release sleeve 38 is Unthreaded completely from the drag body 77, being disposed in the unthreade'd portion of the latter above its internal threads 76. Following engagement of the upper slips 12 with the well casing, an upward pull is taken on the tubing string -D and mandrel 55, which will be transmitted through the apes-,07s

the body 10=to move-.upwardlygcarrying the-lower slips Y231upwardly alongfthelower-.expander l-9 .and shifting them radially outwardly into engagement with-.the well casing, and also-shifting the lower expander 19-and lower slips 23 upwardly toward lthe upper expander 16, foreshortening the `packing sleeve :18-and expandingitzoutwardly into iinm sealing engagement` with .thewallof .the well casing B and the packer body-10. A Sucientrupward stran'is taken on the tubing stringD, mandi-e155, and the body 10 .of the tool-.toinsurethe rm anchoring f the Wickers 13, 25 of the .upper .andi lower seg-mental slips 12, 23 against the vwell casing Band the leakproof sealing of the packing sleeve l18zagainstthe .wallof .the well casing and the body of the tool.

The upward strain on the body of the .tool can` now be relieved, fthe parts externallyofthe body remaining anchored in packed-ol--condition.against-.the well casing by virtue of a vone-way lock device y93 that precludes separation between .the parts. As disclosed, .the Alower portion-ofthe body has-a plurality of'ratchetteeth 94 extending circumferentially therearound andifacing a downward direction, which are adapted to .engagecompanion upwardly facing ratchet' teeth 95`formed internally .an a -split ratchet sleeve 96 disposed within thelowerexpander 19. Theouter surfaceoftheratchet .sleeve 96 consists ofcam teeth 97 tapering-.in adownwardandinward direction and engageable .companion tapered cam teeth 98 formed in theexpander 19. The ratchet 4device 93 will permit the body10 tomoveupwardly through .the lower expander-19,.since .the bodyratchet .teeth 94 will merely ratchet freely overthe companionteeth .95 on the lock sleeve 96. Howevenshould the .body 10 tend to shift downwardly, the ratchet teeth 94, 95 will covengage, and any tendency for the ratchet ringto move downwardly will cause the cam teeth 97,- 98 to .engage and Aurge lthe split ratchet sleeve inwardly, thereby preventing downward movement .offthe body with .respect to the lower expander, the latter being prevented from movingdownwardly since it is wedged within .thelower slips 23 that are .anchored against the wall .of the -well casing.

As a result of the unthreading of the head'75 of the' vrelease sleeve from the drag body-77,the retainingpins 33 will have been elevated above vtheholes 35 in the body ring 11. The mandrel 55 cannow be disconnected Afrom the body 10 of the tool, which is prevented from rotating .by the anchoring action ofthe slips 12, 23 against the well casing. The tubing string D and mandrel 55 are rotated to the right which willl cause the nut 67 to rotate to the right within the threaded box 68 of the body 10. In view of the left-hand threaded connection between the nut and body, the nut will unscrew. from the body, shifting upwardly along the -mandrel E55. During its unthreading action, the rotatable driving connection between the mandrel l55 and nut 67 is retained inview of the spline connection provided between the mandrel .key'69 and the keyway 70 in the threaded nut.

With the well packer anchored in packed-oh condition in the well casing, the desired operation may be performed in the well bore. For example, `a suitable charge ofcement .slurry may be pumped down the tubing string D, passing downwardly through the mandrel' 55 and out through the ports 100 in its lower portion below the valve seat28, ilowing down into the well casing B below the packer and out from the casing into the wellv formation. Such pumping action can occur with or without the nut 67 threadedly secured to the body 10.

When the nut'67 has been Unthreaded from .the.,body, .the tubing string D vand mandrel 55 can be elevated, .to pull the mandrel upwardly within the .body and shifting .theports 100 in the .mandrel aboverthe vlower-seal ring and cylindrical seat 28 in therlower ybody member. The mandrel section below theportslllhas-an end Wall -101.closingzthe mandrel, the uninterruptedfperiphery of .the mandrel below its portssealingagainst: thecylindrical pumpeddovimwardlytthroughthe apparatus to .anyf.further extent, as well .-asjpreventing-such uid from owing .back into the 'tool .throughithe .ports 1100, which are-,now in closed position, such asillustrated in FIG. l6.

The mandrel may be provided with. a lower-valvehead 32 threaded .onto'the lower-.end of a release stud 105, which is, intuirn, .threade'dfintothe lower portion vof the .mandrelsection 58. Thisrrelease fstud .105 has antintermediate weakened section .106 atwhich it will part when isubjected'to a scient tensile strain. 'The head 43-2.has a .tapered surface -107 conforming to thetaperedy surface `of the lower valve -seat 12'9,.so.that.upward movement .of the mandrel 55 toa sufficient extentwill not onlybring its cylindricalsurface` below the ports v100 in engagement with the upper cylindrical valveseat 28 and ring 30,-but lwill also shiftthe lowerhead 32 into `engagement withl the tapered valvefseat 29-and.gasket,.thereby providingitwo .valve seats toinsure against leakage of lluid through` the apparatusbothin upward and downward direction. At any time, the mandrel 55 can be. relowered to` the position determined by engagement of the ilange 63 on the retain- `ingfsleeve 62with .the:s-houlder-64 on the. body-10 to again .remove .the-valve head l32-.from-its` seat 29 and shift vthe Jportsbelow the .cylindrical seat 28, whereupon fluid -now .taken on the tub-ing 'string and mandrel, which .is

transmitted throughthe release'stud 1,05 to the head `.32. When thispullfexceeds the tensilerstrengthof stud atfits weakened section 106, the latter is parted at that point, .allowing the entire mandrel 55 to beremoved from vthe wellv packer A and the entire setting tool C torbe elevated in the well casi-ng by the tubingfstring1D, landsremoved completely'therefrom. The `head .32 will'remain seated against the tapered valveseat 29,.,aszdisclosed in- FIG. 7, acting as a back pressure valvepreventing` upward-flow of iluid back into the passage Y59 jthrough the apparatus.

It is, accordingly, apparent thata-well packer has been provided in which thebody10 of the -tool is imperforalte. .The upper slips 12 are 'retained positively in retracted .position and cannot be moved 'from such retractedposi- .tion until the retainingy pins 33 .are withdrawn-from the .bores y34. The shear screws-17, .20, 24 holding the upper and lower-.expanders 16, 19 vtothe body.10 .and the lower sli-ps 23 to the lower expandert19-.may be'made comparatively strong, resisting premature lshearing or` trippingof the screws and -setting ofthe'.v retainer in the well casing during its lowering therewithin to .the desired setting point. .The pins 33 are positively. removed from .the upper v:slip segments 12 .as `a result of rotation ofthe .apparatuathe packer being lfirmly set bythe taking. of a vsubstantialyand sucient upward strainon thetubing string D, mandrel 55 and body 10 of thepacker. .Fluid can be pumped downwardly through `the set .tool and the .passageV therethrough can be closed wheneverdesired by exerting .an upwardtorce on the vvmandrel which `.will shift the lower head 32.into engagement with its seat.29. The sealingengagement between the head 32 and seat..29. andalso between the lower portion of the mandrel and the cylindrical seat 28 will not only preventupward return ow of .fluid through the apparatus, butit will ,alsopreventdownward -ilow .offluid through theV `apparatus A, which will .then function as .fa fbridgeplug. At anytime the passage through the apparatus can be reopened merely by shifting :the .tubingstring DandmandrelSS downwardly. Finally,

when .the ,setting :portion C .of the .apparatus .is ;tof tbe. kre- -Lmoved fromthe .we111casing, an upwardipull of ay suicient 'stud A105, disconnecting the mandrel 55 from the lower ivalve head 32, which rema-insfengaged with its companion Ytapere'ill seat 29 to prevent upward ow of fluid through Athe well packer. Y p Y The inventors claim:

1. In well apparatus` adapted to be set in a well bore: a body adapted toV be lowered in the well bore on a run- 'ning-in string; normally retracted meanson and shiftable with respect to` said body and expandible laterally outwardly of said-body; spring means for shifting said normally retracted means longitudinallyV ofn said body and laterally outwardly of said body; retainer means secured to said normally retracted means to prevent said spring means from expanding said normally retracted means; and means responsive to rotation of the runningin string to shift said retaining means longitudinally along said normally Vretracted means to a position in which said retaining means is released from said normally retracted means to permit said spring means to shi-ft said normallyretracted means. v 2. In well apparatus adapted to be set in a Well bore: a body adapted to be lowered in the well bore on a running-in string; an expander on said body; segmental slips vengaging said expander; spring means for shifting said slips longitudinally of said expander to expand said slips laterally outwardly of said body; retaining means engaging said slips to. prevent their outward expansion; 'and means responsive to rotation of the running-in string for shiftingV said retaining means longitudinally along said slips to a position in which said retaining means is released from said slips to permit said spring means to shift said slips. 3. In well apparatus adapted to be set in a well bore: Va body adapted to be lowered in the well bore on a running-in string; an expander on said body; segmental slips engaging said expander; spring means for shifting said Vs 1i1ztsrelative to said expander and laterally outwardly of said body; longitudinally movable retaining means engaging said slips to prevent their outward expansion; and means for moving said retaining means longitudinally along said slips to -a position in which said retaining vmeans is released trom said slips to permit said spring means to shift said slips.

4. In well apparatus adapted to be set in a well bore: a body adapted to -be lowered in the well bore on a running-in string; 'an expander on said body; segmental slips engaging said expander and having longitudinally extending |bore therein; spring means for shifting said slips longitudinally of said expander to expand said slips laterally outwardly of said body; retaining means including pins disposed in said bores to prevent said spring meansvfrom shifting said slips outwardly; and means for moving said retaining means longitudinally to remove said pins from said bores to permit said spring vmeans to shift said slips.

5. In well apparatus adapted to be set i-n a well bore: Ya body adapted to be set in the well bore on -a runningin string and having an abutment thereon; an expander on said body; slips engaging said expander vand having longitudinally extending bores therein; spring means engaging said slips and abutment for shifting said slips longitudinally of said expander to expand said slips laterally outwardly of said body; retaining means including pins `extending through said abut-ment into said bores *to prevent said spring means from shifting said slips outwardly; and means for moving said retaining means longitudinally to remo've said pins from said 'bores to permit said spring means to shift said slips.

6. In well apparatus ladapted to be set Yin a well bore: a body; normally retracted means on and shiftable with respect to said body land expandible laterally outwardly 'of said body; 'spring means for expanding said normally retracted meanslaterally outwardly of said body; a man- ,.drel' secured to said body; retaining means seoured to said normally retracted means to prevent said spring means fromy expanding said normally retrated means; and means responsive to rotation Vof; said mandrellfor shifting said retaining means longitudinally along said normally retracted means to a position in whichsaid retaining means is released from said normally retracted imeans to permit said spring means to expand said normally retracted means. s

A7. In well apparatus adapted to beset in a well bore: a body; normally retracted means on and shittable with respect to said body and expandible laterally-*outwardly of said body; spring means for expanding said normally retracted means laterally outwardly of said body; a friction drag device; retaining means threadedly connected to said drag device and secured to said normally retracted means to prevent said spring 4means Yfrom expanding said normally retracted means; and a mandrel secured to said body and adapted to rotate saidn retaining means relative to said drag device to release said retaining means from said normally retracted means to permit said spring means to expand said normally retracted'means.

8. In well apparatus adapted to be set in a well bore: a'body; an expander Yon said body; segmental slips engaging said expander Vand having longitudinally extending bores therein; spring means for shifting said slips longitudinally of said expander to expand said slips laterally outwardlyof said body; a friction dragl device; retaining means threadedly connected to said drag dev-ice and including pins disposed in said bores to prevent said spring means from shifting said slips outwardly; anda mandrel secured to said body and adapted to rotate said Vretaining means relative to said drag dev-ice to remove said pins from said bores to perm-it sai-d spring means to shift said slips.

9. In well apparatus adapted to be set in a well bore: a body adapted to be lowered in the well bore on a rnnning-in string and having an abutment thereon; an expander on said body; slips engaging said expander and having longitudinally extending bores therein; V'spring Y means engaging said slips and abutment 'for shifting said slips longitudinally of said expander to expand said slips laterally outwardly of said body; a friction drag device; retaining means threadedly connected to said drag device and including pins extending through said abutment into said bores to prevent said spring means from shifting said slips outwardly; and Aa mandrel secured to said body and adapted to rotate said retaining means relative to said drag device to move said retaining means longitudinally and to remove said pins from said bores to permit said spring means to shift said slips.

10. In well apparatus adapted to be set in a well bore: a body having an abutment thereon; an upper expander on said body, upper slips engaging said expander and having longitudinally extending bores thereon; a lower expander on said `body; lower slips engaging said lower expander; spring means Vengaging said 4upper slips and abutment for shifting said upper slips downwardly of said upper expander to expand said upper slips laterally outwardly of said body; -a friction drag device above said abutment; retaining means threadedly connected to said drag device and including pins extend-ing through said abutment into said bores to prevent said spring means rom shifting said upper slips outwardly; a mandrel sefcured to said body and adapted to rotate said retaining means relative to said drag device to elevate said retaining means and remove said pins trom said bores to permit said spring means to shift said upper slips; and means on said body engageable with said lower slips to shift said lower slips upwardly alongV said lower expander and laterally outwardly in response tov upward movement of said mandrel and body.

l1. In well apparatus adapted to be set in a well bore:

a tbody adapted to belowered in the well bore on a running-in string; means/,foranehoring said body in the Well bore including a set of initially retracted segmental slips expandible outwardly and capable of moving circumferentially of said body `during outward expansion; transverse aligning pins on said slips, said slips having transverse bores snugly and slidably receiving said pins to maintain said slips in transverse alignment with respect to each other during their outward expansion.

12. In well apparatus adapted to be set in a well bore: a body adapted to be lowered in the ywell bore on a running-in string; means for anchoring said body in the well bore including a set of initially retracted segmental slips expandible outwardly and capable of moving circumferentially of said body during outward expansion; adjacent slips having -aligned transverse bores opening through the Iadjacent ends of said slips; and pins in said transverse bores, said pins being snugly slidable in at lleast some of said bores to enable said slips to expand outwardly while said pins maintain said slips in transverse alignment with respect to each other.

13. In well |apparat-us adapted to be set in a well bore: a body adapted to be lowered in the well bore on a running-insti-ing; normally retracted means on and shiftable with respect to said body and expandible laterally outwardly oi said body; spring means `for shifting said normally retracted means laterally outwardly of said body; retainer means secured to said normally retracted means to prevent said spring means from expanding said normally retracted means; and means responsive to rotation of the running-in string to shift said retaining means longitudinally along said normally retracted means to a position in which said retaining means is released from from said normally retracted means to permit said spring means tol shift said normally retracted means.

14. In well apparatus adapted to be set in a well bore: a body adapted to be lowered in the well bore on a running-in string; an expander on said body; segmental slips engaging said `expander and having longitudinally extending bores therein; spring means for shifting said slips laterally outwardly of said Ibody; retaining means inoluding pins disposed in said bores to prevent said spring means from shifting said slips outwardly; and means yfor moving said retaining means longitudinally to remove said pins from said bores to permit said spring means to shift said slips.

References Cited in the iile of this patent UNITED STATES PATENTS 1,524,288 Burns I an. 27, 1925 2,189,702 Burt Feb. 6, 1940 2,427,330 Spencer Sept. 9, 1947 2,633,917 Baker et al. Apr. 7, 1953 2,681,113 Baker etal June 15, 1954 2,690,225 Baker Sept. 28, 1954 

